Here, using an effective low-energy phenomenological model, we systematically study the diverse magnetic phases induced by the proximity effect in BLG and obtain the corresponding spin polarization near the Fermi energy. Our results indicate that the band spin polarization depends strongly on the layer distribution of magnetism and can always be controlled by gate voltage by turning on or off spin degeneracy and modulating spin-dependent band edges. We further demonstrate that the spin polarization can be modified by staggered sublattice potential originating from the proximity effect and illustrate how the electrically-tunable spin filtering, giant magnetoresistence, and spin diode effects can be visualized in the devices based on magnetic BLG junctions. The all-electrical control of our proposed devices is superior to the magnetic-field control of traditional devices [1]} because the operation is easier. Meanwhile, BLG can be easily integrated into heterostructures [2]}, [3]}, [4]}, and thus our results open new possibilities for developing low-dimensional spin-based devices by fully exploiting the layer degree of freedom.
